A Study Regarding Predictive Factors for Malignancy of Papillary Lesions on Core Needle Biopsy of the Breast

Purpose: Diagnosing benign or malignant papillary lesions of the breast through core needle biopsy (CNB) is often difficult. The purpose of this study was to identify the predictive factors of malignancy. Methods: We retrospectively reviewed the pathology database and found 80 consecutive patients who had been diagnosed with breast papillary lesions prior to surgery at two medical centers from May 2004 through May 2009. Those patients who had undergone CNB and had been diagnosed with either intraductal papilloma or malignant lesions following surgical excision were included. Results: Forty-five cases were diagnosed as intraductal papilloma and 24 cases as malignant lesions. Malignancy was found to be related to being older than 60 years (p<0.01), having bloody nipple discharge (p=0.05), and a tumor size of more than 1 cm (p<0.01). Further, irregular shape (p<0.01) and uncircumscribed margin (p<0.01) on mammogram and irregular shape (p=0.04), calcification (p<0.01), and isoechoic pattern (p<0.01) on ultrasonogram were significantly related to malignancy. Conclusion: Our study revealed that particular clinical factors and imaging findings correlated with malignant lesions. However, larger prospective studies are still necessary to establish treatment plans for patients diagnosed with papillary lesions on CNB.